Device for clamping mouldings for frame assembling machines

ABSTRACT

A clamping device for clamping mouldings for a frame assembling machine having a mobile plate ( 4 ) that carries a straight sliding clamp ( 6 ), returned by a spring and rotary clamp ( 7 ), each adapted to engage one of two mouldings to be clamped and assembled. The sliding clamp ( 6 ) is fixed to a jib ( 8 ) which extends beneath the mobile plate ( 4 ). The rotary clamp ( 7 ) is integral with a spindle ( 9 ) passing through the mobile plate and which bears in its lower part a lever ( 10 ) extending towards the jib ( 8 ) whereto it is fixed by an anchoring pin ( 11 ).

BACKGROUND OF THE INVENTION

The invention relates to a device for clamping mouldings prior tostapling, in a frame assembling machine.

The frames designed to surround pictures are known to be manufacturedfrom framing strips, beads or mouldings by cutting the latter to a mitreshape for subsequent assembly. To assemble these mouldings, use isadvantageously made of a staple formed of a metallic strip bent in twoin the vicinity of its median part, one of the horizontal edges of whichhas a bevelled part formed from the internal face of the staple and thevertical edges of which are bent back outwardly in the direction of thebending axis.

For stapling properly speaking, there is known a machine comprising atable with a 90° notch on its forward face, and means for applying themitre faces of the framing strips against one another under pressure.

More precisely, these means are constituted by a mobile plate, the frontpart of which forms a 90° angle so that its faces move parallel to thoseof the notch, as well as two claws borne by said plate the role of whichis, when the plate is moved forward, to exert a pressure against themouldings and to clamp them in this way against one another and againststops, prior to stapling properly speaking. One of the claws isslideable on the mobile plate, and return biased by a pressure spring.The other claw, which is also return biased by a spring, is pivotable onthe plate and its pivoting movement is produced in the direction ofclamping of a moulding, when the plate itself moves forward, thanks to aprojection serving as a stop.

It is thus the movement of the mobile plate in the direction of thetable bearing the mouldings that causes the action of the claws bytranslation or rotation. The return springs of the claws therefore haveto be calibrated correctly so that the pressure that they exert on themouldings is sufficient but not excessive, and these calibrationoperations prove to be quite a delicate matter. The Applicant has alsonoted that the pressure that the pivoting claw could exert can varyaccording to the dimension of the mouldings and the distance that can begiven to the mobile plate in relation to the fixed table, since theclamping of this pivoting claw is linked to the advance of said plate.

SUMMARY OF THE INVENTION

To avoid these drawbacks and to make these positioning and clampingoperations easier, the Applicant has developed a system with claws whichact only when they are placed in abutment against the mouldings, and nolonger as soon as the displacement movement of the mobile plate occurs,

The main object of the invention is thus a device for clamping mouldingsfor frame assembling machines including a fixed clamping table bearingstops forming between them an angle of approximately 90°, and a platethat is mobile in the direction of the stops, on which are mounted astraight sliding claw biased by a spring, as well as a rotary claw, eachcapable of engaging one of the two mouldings to be stapled, a devicewherein connecting members, connected to the mobile plate, connecttogether the sliding claw and the rotary claw, to slave the rotation ofthe rotary claw to the translation movement of the sliding claw.

More precisely, the connecting members are constituted by a jib to whichthe sliding claw is fixed, and by a lever integral with the rotary clawand which extends in the direction of the jib to which it is fixed by ananchoring pin.

BRIEF DESCRIPTION OF THE DRAWINGS

Other particular characteristics and advantages of the invention willemerge from the description that follows of an exemplary form ofembodiment in which reference is made to the annexed drawings, whichrepresent:

FIG. 1, an overall perspective view of a clamping table;

FIG. 2, a perspective view of the underneath of the mobile plate;

FIG. 3, a vertical cross-sectional view, on a larger scale, of themobile plate.

DETAILED DESCRIPTION OF THE INVENTION

FIG. 1 shows a fixed stapling table 1 bearing stops 2 and 3 formingbetween them an angle of approximately 90° and the inclination andspacing of which can be adjusted by conventional mechanisms, not shown.A mobile plate 4 connected to a mobile bar 5, incorporating a jack, notshown, is capable of moving in the direction of the stops (2, 3). On topof plate 4 are mounted a straight sliding claw 6 and a rotary claw 7,each capable of engaging one of the two mouldings to be stapled.

It can b seen more precisely in FIGS. 2 and 3 that the straight slidingclaw 6 is fixed to a jib 8 which extends beneath mobile plate 4. On theother hand, rotary claw 7 is integral with a spindle 9 which passesthrough the mobile plate and which bears, on its lower part, a lever 10extending in the direction of jib 8, to which it is fixed by ananchoring pin 11.

When the mouldings are in place against stops 2 and 3, the mobile plateis operated to move towards them. As soon as straight claw 6 has reachedthe corresponding moulding, it ceases to move and the continued advanceof plate 4 will cause the pivoting of jib 8, which, via pin 11, willcause lever 10 to rotate about spindle 9, as well as rotary claw 7 whichis integral therewith. Through the effect of this pivoting, the rotaryclaw will, itself, press against the other moulding, in a movement thusdirectly slaved to the translation movement of the sliding claw.According to the calibration of the return spring of the sliding clawand the general pressure of the claws provided by the jack of the mobileplate, the positions of the mouldings will be more finely adjusted toensure perfect matching of the profiles of the two mitre cuts prior tostapling.

This proportionality between the rotation of the rotary claw and thesetting back of the sliding claw in relation to the plate, thanks to theconnecting means described above, facilitates the automatic positioningand clamping of the mouldings, prior to the stapling operations that arecarried out in a conventional manner.

1. A clamping device for clamping moldings for a frame assembly machine,said clamping device comprising a fixed clamping table having bearingstops forming between them an angle of approximately 90°, a mobile platemounted on the table for movement in a direction toward the stops, astraight sliding claw biased by a spring, and a rotary claw both ofwhich are mounted on the plate, each of said claws being capable ofengaging one of two mouldings to be clamped for assembly, connectingmembers connected to the mobile plate that connect together the slidingclaw and the rotary claw, to slave rotation of the rotary claw totranslation movement of the sliding claw.
 2. The clamping deviceaccording to claim 1, wherein the connecting members include a jib towhich the sliding claw is fixed, and a lever integral with the rotaryclaw and which extends in the direction of the jib.
 3. The clampingdevice according to claim 2, wherein the lever is fixed to the jib by ananchoring pin.